muffel furnance

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    Muffle FurnaceDr.Samir Sitaram Tambe

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    IntroductionWhat is a Furnace?Equipment to melt metals

    Casting

    Change shape

    Change properties

    Type of fuel important

    Mostly liquid/gaseous fuel or electricityLow efficiencies due to

    High operating temperature

    Emission of hot exhaust gases

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    Parts1.Burners: raise or maintain chamber

    temperature2.Chimney: remove combustion gases3.Furnace chamber: constructed of

    insulating materials4.Hearth: support or carry the steel.

    Consists of refractory materials5.Charging & discharging doors for

    loading & unloading stock

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    Parts

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    Digital muffle fernis

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    Electric M.F.

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    Barrier Material

    Silica Brick

    >93% SiO2 made from quality rocks

    Iron & steel, glass industryAdvantages: no softening until

    fusion point is reached; high

    refractoriness; high resistance tospalling, flux and slag, volumestability

    Low of expension

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    Operating cycle

    Heat-up timeSoaking time Steady temp GraphForging time

    Fuel use: depends on material andnumber of reheats

    Specific fuel consumption depends

    upon the type of material andnumber of reheats required

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    Type of Furnaces1.Forging FurnaceUsed to preheat billets/ingotsUse open fireplace system with radiation

    heat transmission (Genration of Radiatior).Temp 1200-1250 oCOperating cycle

    Heat-up time

    Soaking timeForging time (adjustment cooling)

    Fuel use: depends on material and numberof reheats

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    Type of Furnaces

    2.Re-rolling Mill Furnace Batch type

    Box type furnace

    Used for heating up scrap/ingots/billets

    Manual charge / discharge of batchesTemp 1200 oC

    Operating cycle: heat-up, re-rolling

    Output 10 - 15 tons/day-?Fuel use: 180-280 kg coal/ton material

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    Type of Furnaces3.Re-rolling Mill Furnace

    Continuous pusher type

    Not batch, but continuous charge and

    dischargeTemp 1250 oC

    Operating cycle: heat-up, re-rolling

    Output 20-25 tons/dayHeat absorption by material is slow,

    steady, uniform

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    Refractory walls of a furnace interiorwith burner blocks

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    Refractory lining of a furnace arc

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    Type of Furnaces4.Continuous Reheating FurnacesContinuous material flowMaterial temp 900 1250 oC

    Door size minimal to avoid airinfiltrationStock kept together and pushed

    Pusher type furnaces

    Stock on moving hearth or structureWalking beam, walking hearth,

    continuous recirculating bogie, rotaryhearth furnaces

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    Precousationduring operation

    To avoid electrical shock,

    1. Be installed by a competent, qualifiedelectrician who insures compatibility

    among furnace specifications,

    2. Always be disconnected from the

    electrical supply prior to maintenanceand servicing.

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    Cont..

    To avoid personal injury:1. Do not stand directly in front of the chamber without wearing a heat resistant face shield, gloves and apron.2. Do not operate or clean furnace without

    proper eye protection.

    3. Do not use in the presence of flammable orcombustible materials; fire or explosion mayresult.

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    Importance over puta

    Cost effectiveAny time operatable

    Can adjust temp.according toneedMinimum heat loss.

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    Research

    In Between M.F. and Puta w.r.t.LohaBhasma

    Results: 1.Efficasy: 2.Partical size:

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    Ref.

    www.google.com.

    Encyclopedia.com

    http://www.google.com/http://www.google.com/
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    Thank u